The present invention relates to a down-the-hole drilling machine. More particularly the invention relates to the guiding of the hammer piston in a down-the-hole drilling machine.
In prior art down-the-hole drilling machines a common reason for breakdown has been that the hammer piston has seized upon bending of the surrounding tube. Such bending is caused because the drill hole becomes bent because of inhomogeneities in the ground. One effort to solve this problem has been to make the hammer piston with short guides. However, this has meant that the guides have been worn down quickly with increased air consumption and had functioning as a consequence.